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851.
Among the myriad of cellular functions played by nitric oxide in the brain, there is increasing evidence that nitric oxide might be a primary player in the program of neurogenesis and neuronal differentiation. We have recently reported that tyrosine nitration of proteins is implicated in the signaling pathway triggered by nitric oxide during NGF-induced neuronal differentiation in PC12 cells. The cytoskeleton becomes the main cellular fraction containing nitrotyrosinated proteins, and the cytoskeletal proteins alpha-tubulin and tau are two of the targets. Here, we have studied the association of nitrated proteins with the cytoskeletal fraction in differentiating PC12 cells following exposure to microtubule depolymerising treatments and found that nitration of the cytoskeleton correlates with the increased microtubule stability underlying the progression of neuronal differentiation. These results suggest a novel functional role for nitrated cytoskeletal proteins in the stabilisation of neurites occurring in differentiated neuronal cells.  相似文献   
852.
Extracellular matrix metalloproteinase inducer (EMMPRIN) was examined on bronchoalveolar lavage fluids (BALFs) and lung tissue from patients with fibrosis (usual interstitial pneumonia-idiopathic pulmonary fibrosis [UIP-IPF], n = 15; diffuse parenchymal lung diseases without IPF characteristics on computerized tomography scan, n = 8) and without fibrosis (n = 6). In UIP-IPF, EMMPRIN staining was increased in areas of fibrosis, mainly in macrophages and in epithelial cells. EMMPRIN was also found in the extracellular medium with significant levels in patients with lung fibrosis compared to subjects without fibrosis. Moreover, macrophages from patients with lung fibrosis spontaneously produce EMMPRIN. These findings show that EMMPRIN is increased in lung fibrosis.  相似文献   
853.
OBJECTIVES AND METHODS: Low free plasma triiodothyronine (fT3) is associated with inflammation and cardiovascular damage in patients with end-stage renal disease (ESRD). We investigated the relationship between fT3, left ventricular systolic function and left ventricular mass in a group of 234 dialysis patients, and modelled the association between fT3 and cardiomyopathy in statistical analyses including both direct (interleukin-6 and C-reactive protein) and inverse (serum albumin) acute phase inflammation markers. RESULTS: Plasma fT3 concentration in dialysis patients was significantly (P < 0.001) reduced in comparison with healthy participants and clinically euthyroid patients with normal renal function. Left ventricular systolic function was depressed (P 相似文献   
854.
855.
The site around ACNA factory (Northern Italy) is characterized by multi-metal contamination, therefore it can be considered as a source of autochthonous plants able to tolerate or accumulate heavy metals (HMs). The hill A5, a waste dump of the chemical factory, was chosen as the study area, in order to assess the metal accumulation ability of the vegetation growing under HM stress. The plant species, biodiversity and health were related to the concentration of HMs in four areas of the hill A5, and to the metal accumulation in shoots and roots. Uptake of HMs occurred at different extent in the various plant species and differed according to the considered organ and metal. Polygonum aviculare hyperaccumulated Hg in the shoot suggesting its possible exploitation in phytoextraction. A number of species, that can be useful in phytoremediation plans, accumulated simultaneously more than two heavy metals both in the shoot and in the root.  相似文献   
856.
To improve the poor prognosis for children with metastatic osteosarcoma (OS), interleukin-2 (IL-2) was added to the standard treatment due to its capacity to activate lymphocytes and differentiate lymphocyte subsets into lymphokine-activated killer (LAK) cells that are capable of recognizing and killing various tumor cells. This study concerns a cohort of unselected patients aged < 18 years with metastatic OS, who were treated with IL-2, high-dose methotrexate, doxorubicin, cisplatin, ifosfamide, LAK reinfusion, and surgery, between 1995 and 2010. Thirty-five patients aged 4–17 years were involved. Thirty-two of the 35 patients underwent surgery on their primary tumor, and 25 had surgery on lung metastases too. Twenty-seven patients received IL-2 plus LAK reinfusion. The median follow-up was 130 months (77–228), and the 3-year event-free and overall survival rates were 34.3 and 45.0%, respectively. Eleven patients remained alive, all of whom achieved a complete surgical removal of the primary tumor and lung metastases (1 patient did not receive lung resections due to complete lung metastases remission). Patients who had a complete surgical remission of the primary and metastatic sites and who responded well to chemotherapy had a better event-free survival. These results confirm the importance of complete surgical remission and point to a noteworthy (though still be ameliorate) survival rate in our series of patients, underling a potential role for immunotherapy with IL-2 and LAK/NK cell activation.  相似文献   
857.
858.

Objectives

This study was aimed at correlating a magnetic resonance index of activity (MaRIA) and a magnetic resonance enterography global score (MEGS) with activity indexes in a paediatric population with Crohn’s disease (CD).

Methods

This retrospective study included 32 paediatric patients (median age 14.5 years, 18 male) with proven CD who underwent magnetic resonance enterography (MRE). A correlation analysis was performed on the MRE-based scores, the simplified endoscopic score for CD (SES-CD), the paediatric Crohn’s disease activity index (PCDAI), and C-reactive protein (CRP) levels. Based on PCDAI, comparison of both global MaRIA and MEGS was made between patients with mild and moderate/severe disease activity.

Results

Global MaRIA correlated with SES-CD (r?=?0.70, p?=?0.001) and PCDAI (r?=?0.42, p?=?0.016). MEGS correlated with PCDAI (r?=?0.46, p?=?0.007) and CRP levels (r?=?0.35, p?=?0.046). MEGS differed significantly (p?=?0.027) between patients grouped by clinical disease severity.

Conclusions

MRE-based global scores correlated with clinical indexes of CD activity. Therefore, they represent a potential useful tool to predict CD activity and severity, as well as a possible promising alternative to endoscopy, to monitor paediatric patients with CD during their follow-up.

Key Points

? MRE is widely used to for accurate assessment of CD.? Global MaRIA and MEGS have been suggested as indicators of CD activity.? Paediatric studies comparing MRE-based global scores with clinical CD activity are lacking.? Such scores can serve as predictors of CD activity/severity in paediatric patients.? MRE offers an alternative to clinical score/endoscopy for paediatric CD monitoring.
  相似文献   
859.
BACKGROUND: Optimization of the conditions for regeneration is a major goal in the management of patients with acute liver failure (ALF). Previous observations suggested that hyperoxygenation of the liver may improve its regenerative capacity. Thus, this study aimed to determine whether an additional supply of oxygenated blood achieved by portal vein arterialization (PVA) is protective in rat ALF caused by toxin administration or hepatectomy. METHODS: Sprague-Dawley rats were subjected or not to PVA after CCl(4) intoxication or extended hepatectomy. PVA was performed by interposing a stent between the left renal artery and splenic vein after left nephrectomy and splenectomy. Liver injury was evaluated by the serum ALT level and necrotic cell count. Hepatocyte regeneration was assessed by calculating the mitotic index and bromodeoxyuridine (BrdU) staining. The 10-day survival was assessed in separate experimental groups. RESULTS: The pO(2) in portal blood increased significantly following PVA. In the CCl(4)-induced ALF, serum ALT levels and necrosis were significantly reduced in arterialized than non-arterialized rats. PVA greatly promotes liver regeneration in both models. Finally, PVA significantly improved survival compared to controls (CCl(4): 100 versus 40%; 90% hepatectomy: 90 versus 30%). Interestingly, in the CCl(4)-induced ALF, survival was 100% even when the shunt was closed after 48 h. CONCLUSION: These data indicate that the additional supply of arterial oxygenated blood through PVA promotes a rapid regeneration leading to the resolution of toxic-induced massive liver necrosis and a faster restoration of liver mass after partial hepatectomy in rats. Thus, PVA may represent a novel tool for optimizing hepatocyte regeneration.  相似文献   
860.
Although it is well established that compromised systolic function predicts cardiovascular (CV) complications in symptomatic and asymptomatic patients with ESRD, it still is unknown whether repeated echocardiographic measurements of systolic function in asymptomatic patients with ESRD is useful for monitoring the evolution of cardiomyopathy in these patients. The prognostic value for CV events of changes in systolic function, as measured by midwall fractional shortening (mwFS) in a cohort of 191 dialysis patients, was tested. Echocardiography was performed twice, 17 +/- 2 mo apart. Changes in mwFS (ch-mwFS) that occurred between the second and the first echocardiographic studies then were used to predict CV events during the ensuing 27 +/- 13 mo. After the second echocardiographic study, 85 patients had incident CV events. In a Kaplan-Meier analysis, there was a graded increase in the risk for fatal and nonfatal CV events across ch-mwFS quartiles (P = 0.005). On multivariate Cox regression analysis, ch-mwFS maintained an independent association with CV outcomes. In this analysis, the risk for CV events was 51% lower in patients who manifested an increase in mwFS (hazard ratio 0.49; 95% confidence interval 0.27 to 0.88; P = 0.02) than in those who had a decrease in mwFS. Changes in mwFS have an independent prognostic value for CV events, and periodic echocardiographic studies of systolic function are useful for monitoring asymptomatic dialysis patients.  相似文献   
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